Buttercream Amounts by Cake Size (6"–12") | Cake Warehouse

There's nothing worse than running out of buttercream part way through a project! TO help you avoid frantically trying to match shades, we've done the maths for how much buttercream you'll need to fill and cover each cake size.

Extra things to keep in mind:

• The ratio is 1 part butter : 2 parts icing sugar as a base, but add vanilla or another flavouring to taste, plus milk or cream to adjust the consistency. Try 3 tbsp (45g) milk/cream and a tsp of vanilla for every 225g (ish) of butter.
• The guide below is for round cakes -- square cakes use more buttercream. Size up for square cakes. If your cake is 6-8", size up by one cake size. If it's 9" or more, size up 2 sizes. Eg. for a 6" square cake, make the 7" buttercream amount. For a 10" square cake, make the 12" buttercream amount.
• Piping on cakes uses more buttercream! Make the extra amount for swirls, but it will vary on your technique and design. Don't be afraid to make a bit more just in case you need it!
• Buttercream stores well in the fridge for a week, or the freezer for 3 months.

How much buttercream for cupcakes?

200g butter and 400g icing sugar will give you 12 generous swirls, with a bit to spare for licking the spoon.